Application of titanium dioxide in arsenic removal from water: A review

► TiO2 can function as both photocatalyst and adsorbent for arsenic removal. ► Various efforts are taken to improve the performance of arsenic removal by TiO2. ► There is a controversy over the TiO2 PCO mechanisms of As(III) for a long time. ► Future needs in TiO2-based arsenic removal technology are proposed.